Field of the Invention
[0001] The present invention relates to the control of a Single Frequency Network, and in
particular to a method for dynamically controlling a Single Frequency Network and
a corresponding Single Frequency Network controller.
Background of the Invention
[0002] In the coverage of a traditional Multiple Frequency Network, a signal is transmitted
by a transmitter in a service area at different frequencies to avoid interference
between neighboring transmitters. A broadcast service such as a Multimedia Broadcast
Multicast Service (MBMS) typically occupies a relatively broad frequency band due
to the large amount of transmitted data. Therefore, the broadcast service is implemented
usually using a scheme of single frequency coverage, i.e. a Single Frequency Network
(SFN), in the prior art.
[0003] In the Single Frequency Network, multiple synchronous radio transmitters at different
sites transmit the same signal at the same frequency concurrently, to implement reliable
coverage of a certain service area.
[0004] First, the Single Frequency Network is advantageous in frequency planning, so that
the precious frequency resources can be saved significantly and the utilization of
the frequency spectrum can be improved. Secondly, in a city with lots of high buildings,
there exist numerous areas without the coverage of a radio signal due to the property
of the radio signal per se regardless of the large transmission power of the single
transmitter station, such an area without the coverage of the radio signal may be
referred to as a blind coverage area or blink area, and can be eliminated in such
a manner that the signal is transmitted over the same frequency at multiple stations
in the Single Frequency Network, to obtain improved coverage. Thirdly, the Single
Frequency Network technologies enable the reduction of costs of the transmitter device
in that multiple transmitters with small power instead of one transmitter with large
power can be adopted by optimizing and adjusting the transmission network (such as
the number and distribution of base stations, the height of transmission antennae,
and transmission power) in the Single Frequency Network, thereby reducing signal radiation
and electromagnetic wave pollution, and improving coverage uniformity; in addition,
the intended coverage can be modified as desired at any time.
[0005] In the Single Frequency Network, merely one frequency band is required for the multiple
transmitters to transmit one signal, so that the frequency resources can be saved
greatly. A User Equipment (UE) can process signals from the multiple base stations
as multi-path signals. It is possible that particular time slots are designated for
the MBMS service. Further, diversity is achieved by the simultaneous transmission
of the multiple transmitters, so that the reliability of the receiver can be enhanced
effectively to obtain the coverage required for reliable service. Additionally, the
transmission network can be adjusted and optimized as desired, so that the total power
consumption can be lowered, and the interference with any other network in the environment
can be reduced.
[0006] At present, the Single Frequency Network is controlled in a static manner in the
prior art, that is, base stations and the number thereof within a given Single Frequency
Network are consistent. Or, the Single Frequency Network can be controlled in such
a dynamic manner that a simple "switch on/off" mode is available, that is, the base
stations within the Single Frequency Network can be managed in the "switch on/off"
mode, and a certain base station is either switched on to implement various services
configured at the Single Frequency Network or switched off to no longer implement
the services configured at the Single Frequency Network. Therefore, it is very difficult
for an operator to effectively optimize wireless network resources in the prior art,
and it is impossible to allocate resources based on service requirements of users.
Summary of the Invention
[0007] An embodiment of the present invention provides a method for controlling a Single
Frequency Network, to enable dynamic control of the Single Frequency Network according
to service requirements of a user.
[0008] An embodiment of the present invention provides a Single Frequency Network controller,
to enable dynamic control of the Single Frequency Network according to service requirements
of a user.
[0009] The method for controlling a Single Frequency Network according to an embodiment
of the present invention includes:
obtaining a service request sent by a User Equipment; and
modifying a Single Frequency Network according to the service request.
[0010] The Single Frequency Network controller according to an embodiment of the present
invention includes:
an obtaining unit configured to obtain a service request sent by a User Equipment;
and
a control unit configured to change a Single Frequency Network according to the service
request.
[0011] With the Single Frequency Network controlling method and the Single Frequency Network
controller according to the embodiments of the present invention, by obtaining the
service request sent by the User Equipment and changing the Single Frequency Network
according to the service request sent by the User Equipment, the Single Frequency
Network can be controlled dynamically, thereby enabling an operator to change the
Single Frequency Network according to service requirements of the user (for example,
a Single Frequency Network is added or removed, or base stations within the Single
Frequency Network are increased or reduced), implementing the optimal configuration
of the wireless network resources, and effectively improving the resource utilization
while satisfying the requirements of the user.
Brief Description of the Drawings
[0012] Figure 1 is a flowchart illustrating an overall procedure of dynamically controlling
a Single Frequency Network according to an embodiment of the present invention;
[0013] Figure 2 is a schematic diagram showing the structure of fields contained in signaling
according to an embodiment of the present invention;
[0014] Figure 3 shows a first application scenario where a Single Frequency Network is newly
added according to an embodiment of the present invention;
[0015] Figure 4 shows a second application scenario where a Single Frequency Network is
newly added according to an embodiment of the present invention;
[0016] Figure 5 shows a first application scenario where a Single Frequency Network is removed
according to an embodiment of the present invention;
[0017] Figure 6 shows a second application scenario where a Single Frequency Network is
removed according to an embodiment of the present invention;
[0018] Figure 7 is a schematic diagram illustrating the structure of a Single Frequency
Network controller according to an embodiment of the present invention; and
[0019] Figure 8 is a schematic diagram illustrating the structure of a control unit in the
Single Frequency Network controller according to an embodiment of the present invention.
Detailed Description of the Embodiments
[0020] An embodiment of the invention provides a method for controlling a Single Frequency
Network, including: obtaining a service request sent by a User Equipment; and modifying
a Single Frequency Network according to the service request sent by the User Equipment.
[0021] Obtaining the service request sent by the User Equipment and modifying the Single
Frequency Network can be implemented by a single function entity in the network, which
is hereinafter referred to as a Single Frequency Network controller for the sake of
description. The network may include a plurality of Single Frequency Network controllers,
and each of Single Frequency Network controllers can control the Single Frequency
Network locally in a distributed manner, or the plurality of Single Frequency Network
controllers can control the Single Frequency Network globally in a centralized manner
in which direct or indirect signaling interfaces need to be provided between the controllers.
[0022] Obtaining the service request sent by the User Equipment can be implemented in various
manners which are not limiting herein. For example, obtaining the service request
sent by the User Equipment can be implemented in the following approaches.
[0023] A first approach: The service request sent by the User Equipment is obtained from
a base station serving the User Equipment.
[0024] For example, the service request, which may include a service identifier corresponding
to the requested service and the service initiation time requested by the User Equipment,
is sent by the User Equipment via an uplink feedback channel to the base station serving
the User Equipment. The Single Frequency Network controller queries all the base stations
periodically to obtain the service request sent by the User Equipments from the respective
base stations. Alternatively, the base station notifies the Single Frequency Network
controller of receipt of the service request sent by the User Equipment, and the Single
Frequency Network controller obtains the service request sent by the User Equipment
from the base station after receiving the notification from the base station.
[0025] A second approach: The service request sent by the User Equipment is obtained from
a core network.
[0026] For example, the service request is sent by a User Equipment to the base station
serving the User Equipment via an uplink feedback channel, and the base station transmits
the service request transparently or forwards the same through a relay node to the
core network for storing. The Single Frequency Network controller obtains the service
request sent by the User Equipments from the core network in a preset period. Alternatively,
the core network notifies the Single Frequency Network controller of receipt of the
service request sent by the User Equipment, and the Single Frequency Network controller
obtains the service request from the core network after receiving the notification
from the core network.
[0027] A third approach: The service request sent by the User Equipment is obtained from
another network entity.
[0028] For example, the service request is sent by the User Equipment via an uplink feedback
channel to the base station serving the User Equipment. The base station forwards
the service request to an MBMS Coordinating Entity (MCE) in the prior art, and the
MCE reports the service request to the Single Frequency Network controller.
[0029] A fourth approach: The service request is sent by the User Equipment to the Single
Frequency Network controller directly.
[0030] In embodiments of the present invention, modifying the Single Frequency Network according
to the service request sent by the User Equipment may include: adding or removing
the Single Frequency Network, and adding the base station to or removing the base
station from an existing Single Frequency Network.
[0031] By taking the MBMS service as an example, detailed expression is provided below to
illustrate how to add or remove a Single Frequency Network according to the service
request sent by the User Equipment and to add the base station to or remove the base
station from the existing Single Frequency Network.
[0032] With reference to Figure 1, an overall flowchart of controlling dynamically the Single
Frequency Network according to an embodiment of the present invention is shown and
includes the following processes.
[0033] Process S101: The service request sent by the User Equipment is received by a Single
Frequency Network controller.
[0034] As described above, in process S101, the service request sent by the User Equipment
can be obtained in a manner including, but not limited to, the first, second, third
and fourth approaches above. The process of receiving the service request sent by
the User Equipment is repeated continuously.
[0035] Process S102: Statistics and analysis of the service request is conducted.
[0036] In process S102, various statistics and analysis modes can be used. For example,
a statistics period can be preset, and the statistics is conducted when a statistics
time point is reached according to the preset statistics period.
[0037] The statistics of the service request is described illustratively below.
[0038] 1) A base station is taken as an object of the statistics.
[0039] In this case, base stations serving the User Equipments requesting for each type
of service are determined, the types of services requested by the User Equipments
pertaining to the same base station are determined, and the number of User Equipments
requesting for the same type of service is calculated, so that a dynamic statistics
table is generated for each base station, as shown in Table 1 below.
Table 1
| Service type identifier |
Number of User Equipments requesting for service |
| The first type of service |
10 |
| The second type of service |
20 |
| ..... |
..... |
| The Nth type of service |
X |
[0040] Likewise, corresponding statistics tables can be generated for other base stations
such as a second base station and a third base station.
[0041] Based on the obtained statistics tables of the various base stations, it is possible
to further calculate a total number of User Equipments pertaining to all of the base
stations that request for a certain type of service, and determine one or more base
stations serving the most User Equipments requesting for a certain type of service.
[0042] 2) A service type is taken as an object of the statistics.
[0043] According to all the received service requests, the involved service types are determined,
and the number of User Equipments requesting for each type of service is calculated.
Further, the base stations serving each User Equipment are determined, the number
of User Equipments requesting for the same type of service at each base station is
calculated, and the base stations are sorted according to the calculated numbers of
the User Equipments, to determine the base station taking the primary responsibility
of providing a certain service.
[0044] The above statistics and analysis methods are merely illustrative, various statistics
and analysis can be carried out depending on particular applications and actual requirements
in the practices, and the invention is not limited to this.
[0045] Process S103: It is determined whether to initiate the control of the Single Frequency
Network according to the statistics and analysis results.
[0046] Initiating of the control of the Single Frequency Network is not necessary if the
current statistics and analysis results are substantially the same as the immediately
preceding statistics and analysis results, and process S106 is performed and the current
control of the Single Frequency Network is terminated; otherwise, process S104 is
performed.
[0047] Process S104: The control of the Single Frequency Network is performed.
[0048] In process S104, the modes of controlling the Single Frequency Network include, but
not limited to:
a first control mode of adding the Single Frequency Network;
a second control mode of removing the Single Frequency Network;
a third control mode of adding the base station to the existing Single Frequency Network;
and
a fourth control mode of removing the base station from the existing Single Frequency
Network.
[0049] Each of the control modes will be described in detail in different application scenarios
in embodiments of the present invention.
[0050] Process S105: Corresponding signaling is sent to the respective base station involved
in the control of the Single Frequency Network.
[0051] For example, signaling is sent to a base station newly added to a certain Single
Frequency Network, a base station switching to another Single Frequency Network, and
a base station removed from its Single Frequency Network, and the signaling can carry
a time stamp, an identifier of a Single Frequency Network controller controlling the
Single Frequency Network, an identifier of the base station, an identifier of the
Single Frequency Network including the base station, and identifiers of services provided
in the Single Frequency Network including the base station. Figure 2 shows a schematic
diagram of the structure of fields contained in the signaling.
[0052] Process S106: The current control of the Single Frequency Network is terminated.
[0053] The above flow is performed again if the next statistics time point is reached.
[0054] Hereinafter, the modes of the control of the Single Frequency Network are described
in particular embodiments with reference to the drawings.
[0055] A first embodiment of adding a Single Frequency Network
[0056] Adding of a Single Frequency Network is applicable to the following scenarios.
[0057] 1) A base station which does not belong to any existing Single Frequency Network
(which is referred to as independent base station for the sake of description) is
added to a new Single Frequency Network.
[0058] Base stations serving User Equipments requesting for one or more types of MBMS services
are determined, and if all or part of the determined base stations are independent
base stations not belonging to any Single Frequency Network, a new Single Frequency
Network is obtained by combining the independent base stations, and one or more of
the requested MBMS services are implemented in the new Single Frequency Network.
[0059] As shown in Figure 3, two Single Frequency Networks are present currently, with a
Single Frequency Network 1 (Referred to as SFN1 for short) including a first base
station (NB1), a second base station (NB2) and a third base station (NB3), and a Single
Frequency Network 2 (Referred to as SFN2 for short) including a fourth base station
(NB4) and a fifth base station (NB5). The sixth base station (NB6) and the seventh
base station (NB7) are independent base stations not belonging to any Single Frequency
Network. Based on the statistics and analysis of the service request sent by the User
Equipment, the base stations NB6 and NB7 are those serving the User Equipments requesting
for a certain MBMS service. In this case, a new Single Frequency Network 3 (SFN4)
which includes the base stations NB6 and NB7 and provides at least the MBMS service
requested by the User Equipments is added.
[0060] After the Single Frequency Network SFN3 is added, mapping relationships between the
Single Frequency Network SFN3 and the base stations NB6 and NB7 within the Single
Frequency Network SFN3 are necessary to be added to the Single Frequency Network controller.
Further, it is necessary to send to the base stations NB6 and NB7 the signaling carrying
a time stamp, an identifier of a Single Frequency Network controller controlling the
Single Frequency Network, an identifier of the base station (NB6 or NB7), an identifier
of the Single Frequency Network (SFN3) including the base station, and identifiers
of services provided in the Single Frequency Network SFN3.
[0061] 2) Base stations are selected to construct a new Single Frequency Network according
to the number of User Equipments requesting for a certain or more types of services.
[0062] As shown in Figure 4, one Single Frequency Network SFN1 including base stations NB1,
NB2, NB3, NB4 and NB5 is present currently. After the statistics and analysis of the
service request sent by the User Equipments, multiple base stations are found to be
involved by User Equipments requesting for a certain MBMS service, the multiple base
stations are arranged in sequence according to the numbers of User Equipments requesting
for the MBMS service, and the first three base stations NB3, NB4 and NB5 serving the
most User Equipments requesting for the MBMS service construct a new Single Frequency
Network SFN2 which includes the base stations NB3, NB4 and NB5 and provides at least
the MBMS service requested by the User Equipments.
[0063] After the Single Frequency Network SFN2 is added, mapping relationships between the
Single Frequency Network SFN2 and the base stations NB3, NB4 and NB5 within the Single
Frequency Network SFN2 are necessary to be added to the Single Frequency Network controller.
Further, it is necessary to send to the base stations NB3, NB4 and NB5 the signaling
carrying a time stamp, an identifier of a Single Frequency Network controller controlling
the Single Frequency Network, an identifier of the base station (NB3, NB4 or NB5),
an identifier of the Single Frequency Network (SFN2) including the base station, and
identifiers of services provided in the Single Frequency Network SFN2. As shown in
Figure 4, since the base stations NB3, NB4 and NB5 within the Single Frequency Network
SFN2 previously belong to the Single Frequency Network SFN1, they need to be removed
from the Single Frequency Network SFN1, as a result, the Single Frequency Network
SFN1 includes merely the base stations NB1 and NB2 after the control of the Single
Frequency Network.
[0064] In the application shown in Figure 4, all the base stations of the new Single Frequency
Network belong previously to another Single Frequency Network. In fact, it is possible
that one or more of the base stations serving most of the User Equipments requesting
for the MBMS service are independent base stations, that is, a part of the base stations
within the new Single Frequency Network belong previously to another Single Frequency
Network, a part of the base stations within the new Single Frequency Network are independent
base stations.
[0065] A second embodiment of removing a Single Frequency Network
[0066] 1) A certain Single Frequency Network is removed and all the base stations within
the removed Single Frequency Network become independent base stations.
[0067] If base stations of a Single Frequency Network are found not providing any service
requested by User Equipments according to the statistics of the service request sent
by the User Equipments, the Single Frequency Network is directly removed. In particularly,
the mapping relationships between the Single Frequency Network and the base stations
within the Single Frequency Network are removed, and a removing signaling is sent
to each of the base stations within the Single Frequency Network to notify the base
station that it does not belong to any Single Frequency Network.
[0068] As shown in Figure 5, two Single Frequency Networks are present currently, with a
Single Frequency Network SFN1 including base stations NB1, NB2 and NB3, and a Single
Frequency Network SFN2 including base stations NB4 and NB5. In this case, base stations
NB4 and NB5 are found not providing any service requested by User Equipments according
to the statistics and analysis of the service request sent by the User Equipments,
the mapping relationships between the Single Frequency Network SFN2 and the base stations
NB4 and NB5 within the Single Frequency Network SFN2, which are stored in the Single
Frequency Network controller, are removed directly, and a removing signaling is sent
to each of the base stations NB4 and NB5 within the Single Frequency Network to notify
the base station NB4 and NB5 that they do not belong to any Single Frequency Network.
[0069] 2) When a certain Single Frequency Network is removed, all or some of base stations
within the Single Frequency Network are moved to another Single Frequency Network.
[0070] When the statistics of the service request sent by the User Equipments shows that
the services requested by User Equipments served by the base stations in a certain
Single Frequency Network have been provided by another Single Frequency Network, depending
on the service requested by the User Equipments served by the base stations in the
certain Single Frequency Network, all or part of the base stations within the certain
Single Frequency Network are added to another Single Frequency Network providing the
same service as new base stations, and the certain Single Frequency Network is removed.
[0071] As shown in Figure 6, three Single Frequency Networks SFN1, SNF2 and SFN3 are present
currently. The Single Frequency Network SFN1 includes base stations NB1 and NB2, and
is providing services including a first type of service, a second type of service
and a third type of service. The Single Frequency Network SFN2 includes base stations
NB3 and NB4, and is providing services including the first type of service, the second
type of service and a fourth type of service. The Single Frequency Network SFN3 includes
base stations NB5, NB6 and NB7, and is providing services including the first type
of service and the fourth type of service. Further, the statistics shows that most
of User Equipments served by the base station NB5 request for the first type of service,
most of User Equipments served by the base station NB6 request for the fourth type
of service, and User Equipments served by the base station NB7 do not request for
any service. In this case, the Single Frequency Network SFN3 may be removed, and the
base station NB5 belonging to the Single Frequency Network SFN3 is moved to the Single
Frequency Network SFN1 or SFN2, the base station NB6 belonging to the Single Frequency
Network SFN3 is moved to the Single Frequency Network SFN2, and the base station NB
7 is removed and becomes an independent base station. Since the base station NB5 can
be moved to either of the Single Frequency Networks SFN1 and SFN2, in practices, the
base station NB5 is moved to either of the Single Frequency Networks SFN1 and SFN2,
or to the Single Frequency Network (e.g. SFN1) which is closer to the base station
NB5 in the geographical position. After such dynamic control, the Single Frequency
Network SFN1 includes the base stations NB1, NB2 and NB5, the Single Frequency Network
SFN2 includes the base station NB3, NB4 and NB6, and the Single Frequency Network
SFN3 is removed.
[0072] To implement the above dynamic control, the Single Frequency Network controller needs
to perform the following processes including:
[0073] - removing the locally stored mapping relationships between the Single Frequency
Network SFN3 and its included base stations NB5, NB6 and NB7;
[0074] - establishing a mapping relationship between the base station NB5 and the Single
Frequency Network SFN1;
[0075] - establishing a mapping relationship between the base station NB6 and the Single
Frequency Network SFN2;
[0076] - sending to the base station NB5 the signaling carrying a time stamp, an identifier
of the Single Frequency Network controller controlling the Single Frequency Network,
an identifier of the base station (NB5), an identifier of the Single Frequency Network
(SFN1) including the base station, and identifiers of services provided in the Single
Frequency Network SFN1; and
[0077] - sending to the base station NB6 the signaling carrying a time stamp, an identifier
of the Single Frequency Network controller controlling the Single Frequency Network,
an identifier of the base station (NB6), an identifier of the Single Frequency Network
(SFN2) including the base station, and identifiers of services provided in the Single
Frequency Network SFN2.
[0078] A third embodiment of adding a base station to a Single Frequency Network
[0079] The base stations serving the respective User Equipments requesting for a certain
type of service (which is hereinafter referred to as first service for the sake of
description) are determined, and ordered in sequence according to the numbers of their
served User Equipments requesting for the first service. Depending on the result of
the ordering of the base stations, one or more of the base stations serving most of
the User Equipments requesting for the first service are taken as new base stations
to be added to a corresponding Single Frequency Network (which is hereinafter referred
to as first Single Frequency Network) providing the first service, for example, the
determined base stations serving the User Equipments may be arranged in a decreasing
order of the numbers of their served User Equipments, and the first one or more base
stations in the ordered sequence of base stations are selected to be added to the
first Single Frequency Network.
[0080] Particularly, if the base station added to the first Single Frequency Network belongs
previously to an original Single Frequency Network, the base station needs to be removed
from the original Single Frequency Network.
[0081] Particularly, if there are multiple Single Frequency Networks providing the first
service, the Single Frequency Network adjacent to the base station serving the User
Equipment requesting for the first service, the Single Frequency Network having the
highest receiving quality, or the Single Frequency Network with the most or least
User Equipments receiving the first service may be selected.
[0082] Adding the new base station to the first Single Frequency Network providing the first
service includes:
[0083] establishing and storing a mapping relationship between the new base station and
the first Single Frequency Network in the Single Frequency Network controller; and
[0084] sending to the new base station signaling carrying a time stamp, an identifier of
a Single Frequency Network controller controlling the Single Frequency Network, an
identifier of the base station, an identifier of the Single Frequency Network including
the base station, and identifiers of services provided in the Single Frequency Network
including the base station.
[0085] A fourth embodiment of removing a base station from a Single Frequency Network
[0086] If the statistics of the obtained information of services requested by User Equipments
indicates that there is one or more base stations to which no service request is initiated
by the User Equipment in a certain Single Frequency Network (which is referred to
as a second Single Frequency Network for the sake of description), or the number of
User Equipments initiating the service requests to the one or more base stations is
lower than a preset threshold, or the product of the number of User Equipments initiating
the service requests to the one or more base stations and the occupied bandwidth is
lower than a preset threshold, then the one or more base stations are removed from
the second Single Frequency Network as removing base stations.
[0087] Removing one or more base stations from the second Single Frequency Network as removing
base stations may include:
[0088] removing the stored mapping relationship between the removing base stations and the
second Single Frequency Network; and
[0089] sending a removing signaling to the removing base stations to notify the corresponding
base stations that they do not belong to any Single Frequency Network.
[0090] The control of the Single Frequency Network has been described in detail through
the above four embodiments. It shall be noted that the present invention is aimed
to provide a solution of dynamic control of the Single Frequency Network, thus, the
particular manner of the dynamic control is not limited to those described in the
embodiments. For example, it is also possible to change the types of the services
provided by the respective Single Frequency Networks as follows:
[0091] The types of services requested by User Equipments served by each of base stations
within a Single Frequency Network are determined according to the obtained information
of services requested by the User Equipments; and one or more types of services are
introduced to the Single Frequency Network if those services are currently not in
the list of services provided by the Single Frequency Network. On the contrary, if
current one or more types of services in the Single Frequency Network are not requested
by the User Equipment, the one or more types of services without being requested by
the User Equipment are removed from the Single Frequency Network.
[0092] According to the above embodiments, if an independent base station is present between
two or more Single Frequency Networks, the independent base station is used to transmit
the same service data at the same time and frequency resources as the geographically
adjacent Single Frequency Network, to avoid effectively the signal interference between
base stations.
[0093] The structure of a Single Frequency Network controller corresponding to the method
according to the embodiments above is shown in Figure 7, and the controller includes:
[0094] an obtaining unit 71 configured to obtain a service request sent by a User Equipment;
and
[0095] a control unit 72 configured to change a Single Frequency Network according to the
service request.
[0096] Preferably, the Single Frequency Network controller may further includes:
[0097] a storage unit 73 configured to store a mapping relationship between the Single Frequency
Network and each of base stations within the Single Frequency Network.
[0098] The control unit 72 has a structure as shown in Figure 8 and includes: a first control
sub-unit 721, a second control sub-unit 722, a base station adding sub-unit 723 and
a base station removing sub-unit 724.
[0099] The first control sub-unit 721 is configured to determine base stations to be included
in a new Single Frequency Network and a new base station to be added to a Single Frequency
Network, and notify the base station adding sub-unit 723 of the determined base station.
[0100] The second control sub-unit 722 is configured to determine a base station to be removed
from a Single Frequency Network and notify the base station removing sub-unit 724
of the determined base station, and determine any base station within the Single Frequency
Network to be removed that needs to be incorporated into some other Single Frequency
Network, and notify the base station adding sub-unit 723 of the determined base station.
[0101] The base station adding sub-unit 723 is configured to add a base station to a Single
Frequency Network to which the base station needs to be added.
[0102] The base station removing sub-unit 724 is configured to remove a base station from
the Single Frequency Network including the base station.
[0103] Preferably, the control unit 72 may further include a third control sub-unit 725
configured to change the type of the service provided by the Single Frequency Network.
[0104] As described above, with the Single Frequency Network controlling method and the
Single Frequency Network controller according to the embodiments of the present invention,
when the service request sent by the User Equipment is received, the statistics and
analysis on the service request is performed to implement the dynamic control of the
Single Frequency Network, which includes adding of a Single Frequency Network, removing
of an existing Single Frequency Network, and adding a base station to or removing
a base station from an existing Single Frequency Network (to enable a substitution
of a base station within the respective Single Frequency Network), so that the operator
can adjust the Single Frequency Network according to the service requirements of users,
enable the optimal configuration of wireless network resources, and improve resource
utilization. Further, various new services can be deployed through the flexible settings
of the Single Frequency Network, the user experience can be further improved, and
the network operation value can be increased.
[0105] It will be appreciated to those skilled in the art that various modifications and
alterations may be made to the present invention without departing from the scope
of the invention. Thus, the invention is intended to comprise all these modifications
and alterations if they fall into the scope of the invention defined by the appended
claims and the equivalents.
1. A method for controlling a Single Frequency Network, comprising:
obtaining a service request sent by a User Equipment; and
modifying a Single Frequency Network according to the service request.
2. The method of claim 1, wherein modifying the Single Frequency Network according to
the service request comprises:
performing control of the Single Frequency Network; and
sending signaling to a base station involved in the control of the Single Frequency
Network.
3. The method of claim 2, further comprising, before modifying the Single Frequency Network
according to the service request:
performing statistics and analysis on the service request; and
determining the initiating of the control of the Single Frequency Network from a result
of the statistics and analysis.
4. The method of claim 3, wherein performing the control of the Single Frequency Network
comprises at least one of:
adding or removing the Single Frequency Network according to the service request;
and
adding the base station to the Single Frequency Network or removing the base station
from the Single Frequency Network.
5. The method of claim 4, wherein adding the Single Frequency Network according to the
service request comprises:
determining one or more base stations serving User Equipments requesting for one or
more types of services; and if one or more independent base stations not belonging
to the Single Frequency Network are included in the one or more base stations, combining
the independent base stations into a new Single Frequency Network, and providing,
by the new Single Frequency Network, the one or more types of services;
or,
after determining one or more base stations serving the respective User Equipments
requesting for one or more types of services, arranging the determined base stations
in a decreasing order of the numbers of the User Equipments requesting for the one
or more types of services that are served by the base stations, and selecting the
first one or more base stations in the sequence of the base stations as one or more
new base stations to be combined into the new Single Frequency Network; and if the
new base stations belong to an original Single Frequency Network, removing the new
base stations from the original Single Frequency Network; and providing the one or
more types of services within the new Single Frequency Network.
6. The method of claim 5, wherein combining the base stations into the new Single Frequency
Network comprises:
establishing a mapping relationship between the new Single Frequency Network and each
of the base stations within the Single Frequency Network; and
sending signaling to each of the base stations within the new Single Frequency Network,
with the signaling carrying a time stamp, an identifier of a Single Frequency Network
controller controlling the Single Frequency Network, an identifier of the base station,
an identifier of the Single Frequency Network including the base station, and identifiers
of services provided in the Single Frequency Network including the base station.
7. The method of claim 4, wherein removing the Single Frequency Network according to
the service request comprises:
if all the base stations of the Single Frequency Network do not provide any service
requested by the User Equipment according to the statistics of the service request
sent by the User Equipment, directly removing the Single Frequency Network; or
when the statistics of the service request sent by the User Equipment shows that each
service requested by the User Equipment served by each base station in a first Single
Frequency Network has been provided by any other Single Frequency Network, depending
on the service requested by the User Equipment served by the base station in the first
Single Frequency Network, adding all or part of the base stations within the first
Single Frequency Network, as new base stations, to the other Single Frequency Network
providing the same service requested by the all or part of the base stations, and
removing the first Single Frequency Network.
8. The method of claim 7, wherein directly removing the Single Frequency Network comprises:
removing a mapping relationship between the Single Frequency Network and each base
station within the Single Frequency Network; and
sending removing signaling to each base station within the Single Frequency Network,
to notify the base station that it does not belong to any Single Frequency Network.
9. The method of claim 7, wherein adding all or part of the base stations within the
first Single Frequency Network to the other Single Frequency Network providing the
same service as the new base stations and removing the first Single Frequency Network
comprises:
adding the new base stations to the respective other Single Frequency Network providing
the same service, and removing the mapping relationship between the first Single Frequency
Network and each of the base stations within the first Single Frequency Network; and
sending signaling to each of the new base stations, with the signaling carrying a
time stamp, an identifier of a Single Frequency Network controller controlling the
Single Frequency Network, an identifier of the base station, an identifier of the
Single Frequency Network including the base station, and identifiers of services provided
in the Single Frequency Network including the base station.
10. The method of claim 7, wherein, in adding the new base stations to the other Single
Frequency Network providing the same service, if there are more than one Single Frequency
Network providing the same service, the new base stations are added to any one of
the Single Frequency Networks providing the same service, or one of the Single Frequency
Networks that is geographically adjacent to the new base stations, or one of the Single
Frequency Networks that has the highest receiving quality, or one of the Single Frequency
Networks that includes the most or least User Equipments requesting for the same service.
11. The method of claim 4, wherein adding the base station to the Single Frequency Network
comprises:
determining one or more base stations serving User Equipments requesting for a first
service, arranging the determined base stations in a decreasing order of the numbers
of their served User Equipments; and
selecting and adding the first one or more base stations in the sequence of the base
stations to a first Single Frequency Network providing the first service as new base
stations, and removing the new base stations from the Single Frequency Network originally
including the new base stations.
12. The method of claim 11, wherein if there are more than one Single Frequency Network
providing the first service, the new base stations are added to any one of the Single
Frequency Networks providing the first service, or one of the Single Frequency Networks
that is geographically adjacent to the new base stations, or one of the Single Frequency
Networks that has the highest receiving quality, or one of the Single Frequency Networks
that includes the most or least User Equipments requesting for the same service.
13. The method of claim 11, wherein adding the new base stations to the first Single Frequency
Network providing the first service comprises:
establishing a mapping relationship between the new base stations and the first Single
Frequency Network; and
sending signaling to the new base stations, with the signaling carrying a time stamp,
an identifier of a Single Frequency Network controller controlling the Single Frequency
Network, an identifier of the base station, an identifier of the Single Frequency
Network including the base station, and identifiers of services provided in the Single
Frequency Network including the base station.
14. The method of claim 4, wherein removing the base station from the Single Frequency
Network comprises:
if the statistics of the obtained information of services requested by the User Equipments
indicates that there is one or more base stations to which no service request is initiated
by the User Equipment in a second Single Frequency Network, or the number of the User
Equipments initiating the service requests to the one or more base stations is lower
than a preset threshold, or the product of the number of the User Equipments initiating
the service requests to the one or more base stations and the occupied bandwidth is
lower than a preset threshold, then removing the one or more base stations from the
second Single Frequency Network as removing base stations.
15. The method of claim 14, wherein removing the one or more base stations from the second
Single Frequency Network as removing base stations comprises:
removing the stored mapping relationship between the removing base stations and the
second Single Frequency Network; and
sending removing signaling to the removing base stations to notify the base stations
that they do not belong to any Single Frequency Network.
16. The method of claim 3, further comprising:
changing the type of a service provided by the Single Frequency Network, wherein the
type of a service requested by the User Equipment served by each of base stations
within the Single Frequency Network is determined according to the obtained information
of the service requested by the User Equipment; and one or more types of services
are introduced to the Single Frequency Network if those services are currently not
in the list of services provided by the Single Frequency Network; or, if current one
or more types of services in the Single Frequency Network are not requested by the
User Equipment, the one or more types of services without being requested by the User
Equipment are removed from the Single Frequency Network.
17. The method of claim 1, wherein if an independent base station not belonging to any
Single Frequency Network is present between two or more Single Frequency Networks
geographically, the independent base station transmits the same service data at the
same time and frequency resources as the geographically adjacent Single Frequency
Network.
18. The method of any one of claims 1-17, wherein obtaining the service request sent by
the User Equipment comprises:
obtaining the service request sent by the User Equipment from a base station serving
the User Equipment; or
obtaining the service request sent by the User Equipment from a core network after
the service request is transmitted transparently through the base station to the core
network; or
obtaining the service request sent by the User Equipment from a MBMS Coordinating
Entity.
19. A Single Frequency Network controller comprising;
an obtaining unit configured to obtain a service request sent by a User Equipment;
and
a control unit configured to change a Single Frequency Network according to the service
request.
20. The Single Frequency Network controller of claim 19, further comprising:
a storage unit configured to store a mapping relationship between the Single Frequency
Network and each of base stations within the Single Frequency Network.
21. The Single Frequency Network controller of claim 20, wherein the control unit comprises
a first control sub-unit, a second control sub-unit, a base station adding sub-unit
and a base station removing sub-unit,
the first control sub-unit is configured to determine the base station to be included
in a new Single Frequency Network and the base station to be added to an existing
Single Frequency Network, and notify the base station adding sub-unit of the determined
base station;
the second control sub-unit is configured to determine the base station to be removed
from the Single Frequency Network and notify the base station removing sub-unit of
the determined base station, and determine any base station within the Single Frequency
Network to be removed that needs to be incorporated into any other Single Frequency
Network, and notify the base station adding sub-unit of the determined base station;
the base station adding sub-unit is configured to add a base station to a Single Frequency
Network to which the base station needs to be added; and
the base station removing sub-unit is configured to remove a base station from the
Single Frequency Network including the base station.
22. The Single Frequency Network controller of claim 21, wherein the control unit further
comprises a third control sub-unit configured to change the type of the service provided
by the Single Frequency Network.